JFK 19/3 Snow and de-icing
JFK 19/3 Snow and de-icing
Finally found the time to put some pics (poor quality but the weather was really bad) of de-icing activity @ JFK during heavy snowfall on Friday evening 19/3. Pics taken while waiting to board SN502 to BRU...
De-icing of our own A330 took approx. 45 minutes. No time for a flight report but trust me, SN's economy class product was really decent. I would fly them again, also long haul.
Cheerz,
Capetown
De-icing of our own A330 took approx. 45 minutes. No time for a flight report but trust me, SN's economy class product was really decent. I would fly them again, also long haul.
Cheerz,
Capetown
Re: JFK 19/3 Snow and de-icing
The reason why the de-icing is a two step process, is because the first fluid used is probably a Type I fluid, which is used to de-ice the aircraft (it removes the ice/snow). However, if there was no other treatment after that, there would be no protection against ice forming again. That's why a second (Type IV, probably) liquid is used as an anti-ice liquid. The Type IV liquid is also more viscous than the Type I liquid, causing it to "stick" to the aircraft during the take-off roll.
Thomas
Re: JFK 19/3 Snow and de-icing
Thanks for nice explanation, KriVa. I've never seen such a process in Europe though. Is it reserved for very bad weather, like in JFK on 19/03 ?
By the way, capetown, thanks for posting this unusual experience.
By the way, capetown, thanks for posting this unusual experience.
André
ex Sabena #26567
ex Sabena #26567
Re: JFK 19/3 Snow and de-icing
I have to be honest, my currency on winter operations is somewhat lacking, so some things are a bit hazy.
However, if I seem to remember it correctly, the combination of Type I+ Type IV is used when Type IV itself (which is both a de-icing and an anti-icing fluid) would be insufficient. So, like you said, when the weather turns really nasty.
However, if I seem to remember it correctly, the combination of Type I+ Type IV is used when Type IV itself (which is both a de-icing and an anti-icing fluid) would be insufficient. So, like you said, when the weather turns really nasty.
Thomas
Re: JFK 19/3 Snow and de-icing
I've had 2 step de-icing quite a few times in the more northern regions of europe
Re: JFK 19/3 Snow and de-icing
2-step is quite common here actually. Done is several times this winter all over western and northern europe. The uncommon thing is type IV, never used it actually. Only combo of I and II (translucent color).
Re: JFK 19/3 Snow and de-icing
Right, I must've been someplace else mentally yesterday. Type IV is hardly ever seen at airports like BRU (weather-wise), while types I-II are more common.
In any case, it's been a while since I last had some winter ops training, so it's all a bit hazy. Thanks for correcting me in any case!
In any case, it's been a while since I last had some winter ops training, so it's all a bit hazy. Thanks for correcting me in any case!
Thomas
Re: JFK 19/3 Snow and de-icing
I am not a specialist on winter-ops/deicing but it looks very strange a truck would hold 2 different types of deicing-fluids. I thought 2step deicing was step 1 : deicing . step 2 anti-icing. If memory serves well the difference is in the mixture of the fluid (water vss deicing fluid) depending the actual weather conditions.
motorcycling : sensation with a twist of the wrist
Re: JFK 19/3 Snow and de-icing
I may be wrong, of course, but I do seem to remember that different liquids contain different agents, making them more or less suitable for one job or the other (de-icing vs. anti-icing).
I also seem to remember the dilution with water being based on something else, but I can't remember how that was decided.
I also seem to remember the dilution with water being based on something else, but I can't remember how that was decided.
Thomas
Re: JFK 19/3 Snow and de-icing
Actually, I've had the first step being just hot water and second step type II.
Fluid decision is a combination of the precipitation, required holdover time (%) and the LOUT (lowest operational usage temperature) to maintain a 7 degree buffer to the fluid freezing point. (10 degree for type I).
That last one can be tricky, your wing temperature can be lower than the OAT, so lowest one counts.
Fluid decision is a combination of the precipitation, required holdover time (%) and the LOUT (lowest operational usage temperature) to maintain a 7 degree buffer to the fluid freezing point. (10 degree for type I).
That last one can be tricky, your wing temperature can be lower than the OAT, so lowest one counts.
Re: JFK 19/3 Snow and de-icing
Thanks Kriva and others for posting these interesting comments about a process I (being a layman) hadn't a clue about...
Re: JFK 19/3 Snow and de-icing
There is an interesting article about aircraft deicing fluids (the four types) in Wikipedia:
https://en.wikipedia.org/wiki/Deicing_fluid
https://en.wikipedia.org/wiki/Deicing_fluid
André
ex Sabena #26567
ex Sabena #26567